"The stain of sexual abuse allegations against United Nations peacekeepers resists removal three years after sickening reports of soldiers' predatory behavior in the Central African Republic (CAR). That much is clear from an internal report detailing the glacial bureaucracy in investigating, reporting and tracking these horrific accusations.

What remains unclear is whether the U.N. is ever going to eradicate this longstanding cancer that has infiltrated peacekeeping forces in CAR, Haiti and elsewhere.

The 23-page report from the U.N.'s Office of Internal Oversight Services documents a lackadaisical regard not just in prosecuting allegations of abuse but also in providing basic assistance and safety for victims. More than half of the 37 U.N. bases in CAR have been flagged for potential problems, The Washington Free Beacon reports.

Meanwhile the leadership of the CAR peacekeeping force (known as MINUSCA) still hasn't produced a system that encourages victims to resist and report sexual abuse in what's been called a 'culture of impunity,' according to Fox News.

Such disregard is hardly surprising after top U.N. officials initially attempted to cover up the scandal in CAR - then punished the whistleblowers..."

One eyewitness told the BBC: "I saw there were multiple trucks or jeeps driving through my street, with... local army/police officers with AK47s, deploying in front of my house.

"I heard a lot of shootings and then I was scared as hell and I went inside. I've been hearing quite a bit of shooting."

Analysis: Alex Duval Smith, BBC News, Dakar

A terrorist attack in the Sahel had been expected.

Residents of Burkina Faso's capital had noticed more police road blocks in the past few days. In neighbouring central Mali, the UN mission, Minusma, had requested that staff and contractors avoid using rural roads.

Burkina Faso is part of the Sahel region, which includes Mali where Islamist groups have been active since 2012.

For nearly two years now northern Mali's terrorist challenge has grown into a regional problem, with attacks by al-Qaeda affiliates in Burkina Faso, Niger and Ivory Coast.

Even though the Ouagadougou attack was not prevented, the fact that Mali and Burkina Faso were on alert suggests Minusma's intelligence-gathering operation is bearing fruit.

France is spearheading fundraising for a regional anti-terror force, the G5 Sahel, which will draw from the armies of Mauritania, Chad, Burkina Faso, Mali and Niger.

The force will not be operational until later this year.

The Turkish and French governments confirmed that they had lost one national each in the assault.

French President Emmanuel Macron condemned the attack and said he would hold talks with his Burkinabe counterpart, Roch Marc Kabore, to "evaluate the situation".

The attack is similar to one in January 2016, when gunmen targeted the Splendid Hotel and the Cappuccino restaurant, only 200m further along Kwame Nkrumah Avenue from the scene of the latest attack.

More than 170 people were taken hostage and 30 were killed. The al-Qaeda in the Islamic Maghreb (AQIM) group said it had carried out that attack.